The present invention relates to a socket for use in attaching an IC to a circuit board detachably.
As electronic techniques have been developing rapidly, there has been an ever increasing demand for integrated circuits each having a reduced chip size in spite of its increasing degree of integration. Accordingly, the number of input/output terminals increases more and more, and the space between adjacent conductor patterns on a printed circuit board is reduced less and less.
In case that integrated circuits are produced for trial or in small lots it is required that each of the so produced integrated circuits be so attached to a circuit board as to be changed one after another. A selected integrated circuit is fixed to the circuit board by soldering its pins to selected conductors in the circuit board. When removing the integrated circuit from the circuit board for changing, it is necessary to remove the solder completely from the integrated circuit, but this work is difficult, and the difficulty will increase with the increase of the number of pins, and hence, with the reduction of pin-to-pin interval. Pins are often bent or deformed when removing integrated circuits from the circuit board. An integrated circuit cannot be changed on the circuit board without difficulty.
The present invention aims at the solving of the problems above described, and the object of the present invention is to provide an IC mount device which permits an IC to be detachably attached to a circuit board without difficulty, requiring no soldering.
An IC socket according to the present invention is constructed as follows:
A circuit board has a conductor pattern formed thereon, the conductor pattern having conductors arranged at the same interval as the terminal pins of an IC; a fixture frame has a rectangular window opening formed therein, and it is fixed to the circuit board with its window frame surrounding the conductor pattern; the IC is put in the window opening of the fixture frame, allowing its terminal pins to he on the conductors of the conductor pattern; a rectangular intermediate frame has a window opening and linear ridge-like retainers integrally formed round the window opening, the linear ridge-like retainers being spaced apart from each other at their opposite ends, and the intermediate frame is put on the fixture frame with the linear ridge-like retainers inserted in the window opening of the fixture frame, running along the inner side edges of the fixture frame and lying on the terminal pins of the IC; an uppermost frame is put on the intermediate frame to be fixed to the fixture frame by inserting fastening screws in the through holes made at the four corners of the uppermost frame whereas the intermediate lengths of the linear ridge-like retainers are pushed with pushing screws, which are inserted in the four sides of the uppermost frame until their ends appear on the bottom of the uppermost frame to push the linear ridge-like retainers, thereby pushing the terminal pins of the IC against the conductors of the conductor pattern.
The intermediate frame has linear slots made on its bottom, the linear slots running along the linear ridge-like retainers whereas the fixture frame has fitting projections formed on its upper surface, which fitting projections are allowed to be fitted in the linear slots of the intermediate frame when it is put on the fixture frame.
The inner spaces of the fixture frame, intermediate frame and uppermost frame are larger than the IC body to allow the terminal pins of the IC to be exposed at their base parts.
The intermediate frame has slots formed on its bottom, extending parallel to the ridge-like retainers, and the fixture frame has ridges formed on its top surface to be fitted in the slots of the intermediate frame when being put on the fixture frame.
The rectangular fixture frame has a guide slot made in each corner, thereby permitting the corners of the IC to be guided when being put in the fixture frame.
Each guide slot is inclined outward.
The inner spaces of the fixture frame, intermediate frame and uppermost frame are larger than the IC body to allow the terminal pins of the IC to be exposed at their base parts.